Speaking to a closed fundraiser in San Francisco, California, in early April, Obama said decades of lost jobs and unfulfilled promises from Washington have left some Pennsylvanians "bitter" and clinging "to guns or religion or antipathy to people who aren't like them, or anti-immigrant sentiment or anti-trade sentiment as a way to explain their frustrations."

McCain, campaigning in Pennsylvania on Wednesday, told reporters that his campaign is "going to go into the small towns in the state of Pennsylvania. And we're going to tell them that we don't agree when Sen. Obama said that they cling to guns and religion because they're bitter about the economy."

The "bitter" controversy erupted less than two weeks before Pennsylvania's presidential primary. At the time, Sen. Hillary Clinton blasted Obama as "elitist"

Clinton,Obama's primary opponent at the time, called him on April 13 an "elitist, out of touch and frankly, patronizing." A day later she said "People don't need a president who looks down on them."

"This is the same person who took money from financial folks on Wall Street and then voted for a bankruptcy bill that makes it harder for folks right here in Pennsylvania to get a fair shake," Obama said on April 14. "Who do you think is out of touch?"

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And that comment may have helped Clinton win over the working-class vote. In the Democratic primaries, Clinton ended up beating Obama two to one among white, non-college voters, according to a CNN exit poll -- 62 percent to 31 percent, with 7 percent voting for others.

So how is Obama doing with those voters against John McCain? Not too well.

McCain is winning white, non-college voters by 13 points -- 53 percent to Obama's 40 percent -- according to a CNN/Opinion Research Corp. Poll taken June 26-29. The poll had a sampling error of plus or minus 6 percentage points.

McCain also told reporters Wednesday that his campaign is going to tell these voters that "we love them and we appreciate them and that they're the heartland of America."

But McCain may see a backlash against a comment made by his chief economic adviser and campaign chairman Phil Gramm.

He told the Washington Times Thursday that "we have become "a nation of whiners," adding that "You've heard of mental depression; this is a mental recession. We may have a recession; we haven't had one yet."

McCain campaign spokesman, Brian Rogers, said in a statement: "Phil Gramm's comments are not representative of John McCain's views. John McCain travels the country every day talking to Americans who are hurting, feeling pain at the pump and worrying about how they'll pay their mortgage. That's why he has a realistic plan to deliver immediate relief at the gas pump, grow our economy and put Americans back to work."

On Thursday, Gramm clarified his comments to CNN's Dana Bash.

"The whiners are the leaders, hell, the American people are victims, but it didn't quite come out that way in the story," Gramm said.

Gramm said he was trying to say the problem is leaders who "blame speculators and oil companies for our problems, instead of presenting concrete programs for using energy more efficiently, or leaders who don't think we can compete with Mexico. ... What we need is more leadership and less whining."

When asked which leaders he was referring to, he said, "There are all kinds of them, Congress is full of them, and we have plenty on the national scene."

Gramm, meanwhile, stood by his comments on the country being in a "mental recession."

"I said we are in a mental recession. We keep getting the steady drum beat of bad news. ... It's become a mental recession. We don't have measured negative growth. That's a fact, that's not a commentary," he said.

So are there lingering effects of "bittergate?" Maybe not.

In 2004, long before bittergate," Sen. John Kerry lost white, non-college Democrats by 23 points -- 38 percent to George W. Bush's 61 percent -- according to CNN's exit poll.

In fact, Democrats don't usually do very well with white working-class voters any more: Jimmy Carter lost them in 1980; Walter Mondale in 1984; Michael Dukakis in 1988; Al Gore in 2000; Kerry in 2004.

All those Democrats got defeated. The good news for Obama is that he is not doing as badly as they did with the white working class.

The only Democrat who's won since 1980 is Bill Clinton. How did he do with white working-class voters?

According to CNN exit polls, there was nearly a tie with the first President Bush in 1992 -- 39 percent to 38 percent; and again with Bob Dole in 1996 -- 44 percent to 43 percent.

To keep his blue-collar support down, Republicans are trying to paint him as a social elitist in the tradition of Dukakis and Kerry.

To pump it up, Obama is running as an economic populist in the tradition of Bill Clinton -- and a lot of Democrats think putting Hillary Clinton on the ticket could help Obama with those working-class voters.